Sirius (Alpha Canis Majoris)
Sirius is also known as the Dog Star due to the constellation that the star is located in. It is a double star, the main star is a blue star with an orbiting white dwarf. Part of why it is so bright is that it is one of the closest stars to our solar system. It is visible in the early part of the year and highest in the sky in february / march time based on viewing about 9 p.m. It can be seen earlier in the night but lower down.
Canopus (Alpha Carinae)
The more southern you are, the more likely you are to be able to see this star, the second brightest. Sirius is twice as bright as the next star, Canopus. As the star is moving away from us, its brightness will dim over time.
Rigil Kentaurus (Alpha Centauri)
Rigil Kentaurus is the second closest star to our solar system, the first being Proxima Centauri. Proxima is a Red dwarf star and cannot be seen from Earth without a telescope which is why it is not on the list. Rigil is similar to our own Sun in terms of Spectral Type and size. Unlike the Sun, Rigil is a multiple-star system, there are three stars close together.
It was once thought that the star had an orbiting planet but that has since been disproved. Proxima Centauri has been discovered to have a planet in orbit round it. Proxima sadly is a Flare Star which means that its planet be hit by damaging solar flares, sterilising the planet of any possible life.
Arcturus (Alpha Bootis)
Arcturus is the brightest star in the northern celestial hemisphere. Up until now, all the brightest stars had been in the southern hemisphere. It is an old star and therefore has moved out of its main sequence phrase, that is the phase in which it was converting hydrogen into helium. It is also the largest star in the constellation.
Vega (Alpha Lyrae)
Vega is one of the most well known stars in the northern hemisphere. It is memorable because unlike our own star, the Sun, Vega is not spherical but is more oval but its not yet been established why. Regulus is another oval/egg shaped star but unlike Vega, Regulus is a multiple star system with four stars including the main star. Regulus's shape can be attributed to it being pulled in a oval shape by the gravity of the other stars but Vega is alone. It is believed that there might be a planet in orbit around the planet but none have so far been discovered.
Vega is the first brightest star that has a positive apparent magnitude as all the previous stars were negative values. The smaller, the number, the brighter the star.
Capella (Alpha Aurigae)
Capella is a double double star system, that is four stars separated into two pairs. The two brightest are known as Capella Aa and Capella Ab. The third and fourth are known as H and L. Hipparcos mostly didn't differentiate between stars in multiple systems which is why Capella is recorded as a M type star.
Rigel (Beta Orionis)
Despite being the brightest of the stars in the constellation of Orion, it only has the Beta designation. It is one of the easiest stars to locate, being at the foot of the constellation. It is easy to spot during the winter months. Close to the star is the Witch Head Nebula which is lit up by the star. The Nebula is located in the constellation next to it, Eridanus.
Procyon (Alpha Canis Minoris)
Procyon is the brightest of the two stars that make up the Canis Minoris or smaller dog constellation. The other star is Gomesia. It is not the smallest constellation by area size though. Procyon is a yellow star that is about half to a third the age of the Sun. The star is a double star, the second star is a white dwarf star.
Achernar (Alpha Eridani)
Achernar is at the southern end of the constellation, and is the star that is farthest away from its Beta star, Cursa. The star is another oval shaped star like the previous Vega. Achernar is not visible in the northern hemisphere, you would need to go south of Dallas Texas according to Wikipedia.
Betelgeuse (Alpha Orionis)
Betelgeuse, pronounced beetle juice is one of the more well known stars in the night sky, partly due to its strange and macabre sounding name. It is a large red dying star which has moved out of its main sequence phase and onto the next. It is a star that is expected to go supernova soon ( million years which is soon in astronomy ). When it does go, Earth will be too far away to be affected by the explosion.
No planets have been detected in orbit round this star but there is a belief that the star has consumed a planet that had been in orbit. The bigger a star is, the less effect on it a planet has so its going to be hard to spot any surviving planets in orbit round it.
The next ten brightest stars
Notable stars in the list are Aldebaran, Pollux and Fomalhaut as those three been discovered to have orbiting planets. Pollux is another instance where the brighter star doesn't have the Alpha designation. Castor is a multiple star system which has given the illusion it is brighter.
Hadar (Beta Centauri)
Altair (Alpha Aquilae)
Acrux (Alpha Crucis)
Aldebaran (Alpha Tauri)
Antares (Alpha Scorpii)
Spica (Alpha Virginis)
Pollux (Beta Geminorum)
Fomalhaut (Alpha Piscis Austrini)
Deneb (Alpha Cygni)
Mimosa (Beta Crucis)
What is based on:::::::
The list is based on the apparent magnitude that was recorded in the Hipparcos data library. Apparent magnitude is the scale of how bright an object is as seen from Earth. Another magnitude that gets mentioned is the absolute magnitude which is the score of how bright an object is when we are 32.6 light years away from it. An object that is dim on the apparent magnitude could therefore be much brighter when you closer to it.
0 Comments